Poly vinylidene chloride ("PVDC") coated polyester fills are known and are often used as heat-sealable packaging fills. However, halogenated fills and coatings are increasingly coming under environmental attack and are being subjected to increasing government regulation.
One possible solution to these problems is to replace the PVDC heat seal coating with other heat seal compositions. However, many heat seal compositions can be problematic. For example, copolyesters generally have a relatively narrow heat sealing range: 1. below this range the packaged product may have a tendency to leak; and 2. above this range, the packaged fill can be difficult to open or be subject to unwanted tearing when heat seals were pulled apart.
The present invention is an innovative solution to the above problems.